Discharge lamp, discharge lamp socket, discharge lamp device, and discharge lamp lighting device

Abstract

A discharge lamp is constructed by attaching a base to an outer tube, the base has a spiral feed member and a dotted feed member, and the shortest creeping clearance distance between the spiral feed member and the dotted feed member is defined to at least 6.0 mm. A socket for discharge lamp is constructed by providing a spiral receiving member and a contact piece in an insulating socket body, and the shortest clearance distance between the spiral receiving member and the contact piece is defined to at least 5.0 mm. A socket for discharge lamp is constructed by providing a spiral receiving member and a contact piece in an insulating socket body, and the shortest clearance distance between a socket reference line and the contact piece is defined to at least 19.6 mm.

1 . A discharge lamp constructed by housing an arc tube having a pair of discharge electrodes in an interior of an outer tube having a sealed part at a one-end thereof and attaching a base to the one-end of the outer tube, and lighted by ignition voltage of 2.0 to 3.5 KVrms or pulse voltage of 3 to 5 KV in terms of maximum pulse height, and 
 the base has an insulating base body having a feed member-supporting part and a projected part protruding and extending from a distal end of the feed member-supporting part, a spiral feed member provided on an outer periphery of the feed member-supporting part, electrically connected to one of the pair of the discharge electrodes and having a width of 10.4 to 11.0 mm, and a dotted feed member provided on a tip end of the projected part and electrically connected to the other of the pair of the discharge electrodes,    wherein, in the base, the shortest creeping clearance distance between the spiral feed member and the dotted feed member along an outer surface of the projected part of the base body is defined to at least 6.0 mm.    
   
   
       2 . A socket for discharge lamp, into which a base part provided on a discharge lamp lighted by ignition voltage of 2.0 to 3.5 KVrms or pulse voltage of 3 to 5 KV in terms of maximum pulse height is received, and 
 a cylindrical and spiral receiving member, into which a spiral feed member in the base part of the discharge lamp is screwed, and a contact piece, with which a dotted feed member in the base part is brought into contact, are provided in an insulating socket body,    wherein the shortest clearance distance between the spiral receiving member and the contact piece is defined to at least 5.0 mm.    
   
   
       3 . A socket for discharge lamp, into which a base part provided on a discharge lamp lighted by ignition voltage of 2.0 to 3.5 KVrms or pulse voltage of 3 to 5 KV in terms of maximum pulse height is received, and 
 a cylindrical and spiral receiving member, into which a spiral feed member in the base part of the discharge lamp is screwed, and a contact piece, with which a dotted feed member in the base part is brought into contact, are provided in an insulating socket body,    wherein, when a base part satisfying the conditions of the E11 base prescribed in Japanese Industrial Standards is received, the shortest clearance distance between a socket reference line conforming to a base reference line of a base making up the base part and the contact piece is defined to at least 19.6 mm.    
   
   
       4 . A discharge lamp device comprising the discharge lamp according to  claim 1  and a socket for discharge lamp, into which the base part provided on the discharge lamp is received, and 
 the socket for discharge lamp is constructed by providing a cylindrical and spiral receiving member, into which a spiral feed member in the base part of the discharge lamp is screwed, and a contact piece, with which a dotted feed member in the base part is brought into contact, in an insulating socket body,    wherein, in the socket for discharge lamp, the shortest clearance distance between the spiral receiving member and the contact piece is defined to at least 5.0 mm, and when a base part satisfying the conditions of the E11 base prescribed in Japanese Industrial Standards is received, the shortest clearance distance between a socket reference line conforming to a base reference line of a base making up the base part and the contact piece is defined to at least 19.6 mm.    
   
   
       5 . A discharge lamp lighting device comprising a lighting circuit for lighting the discharge lamp according to  claim 1  at a lighting frequency of 50 Hz to 100 kHz.